Sale! FS-60E High Quality Fusion Splicer Welding Splicing Machine $650.00 $599.00 Rack mount ODF is usually modularity in design with firm structure. It can be installed on the rack with more flexibility according to the fiber optic cable counts and specifications. This kind of optical distribution system is more convenient and can provide more possibilities to the future variations. Most of the rack mount ODF is 19”, which ensures that they can be perfectly installed on to the commonly used standard transmission rack.